That Old Serpent
by Dyskolos
Summary: When Castiel's body starts to give out, Lucifer visits Sam's dreams to get his true vessel back. Both Sam and Dean are breaking down as the hits keep on coming, and to expel Lucifer from Sam's head once and for all, they'll both need to remember who they really are. Hurt/Awesome Sam, Angsty/Protective Dean. Set after "Red Meat." Three-shot.
1. Genesis

_Warning for language, implied physical and sexual violence. This was written before "Hell's Angel."_

 _Bible verses are from the King James Bible, with some slight modifications._

That Old Serpent

 _Now the_ _serpent_ _was more subtle than any beast of the field which the Lord God had made._

 _Genesis 3:1_

Sam stares down into the sundrenched pool before him, watching a school of tiny silvery fish dart through the water, making little bright flashes of light. With the wind blowing salty spray into his face, he follows the fishes' path, crawling over the rocks to the next pool, and this time he sees a bright red starburst resting on the bottom.

"Dean, look!" He calls over his shoulder to where Dean is kicking up sand on the beach. "It's a starfish!"

Dean hops nimbly across the rocks over to Sam, peering down into the pool. "Uh-oh," he says. "That's not a starfish."

Sam blinks up at Dean, squinting against the bright sun. "Yeah, it is, Dean."

"Nope," Dean shakes his head. "You better watch it, Sammy. That looks like a baby kraken to me."

Sam snorts. "You're so full of shit, Dean."

"Hey, _language_ , shortstack."

"Oh, sorry. You're so _fucking_ full of shit, Dean."

Dean starts to scold him again, but he can't do it without laughing so he stops. Sam reaches down into the pool, sending ripples through his shimmering reflection. The water is nice and warm on the top but biting cold underneath. He carefully strokes his fingers across the starfish. It's bumpy and coarse, not slimy like he thought it would be, and it doesn't seem to mind being touched much.

"Dude, gross. Don't touch it."

"It's okay, it—"

Sam breaks off with a gasp, jerking back his hand and splattering the rocks with icy droplets. A long twisty black creature has emerged from the rocks and is gliding over the surface of the water. He tips backward off his heels, and he can't explain why he's so frightened by the thing's gleaming black eyes.

"What?" He feels Dean step closer to him, feels the warmth of his brother's presence, but it doesn't make him feel safe like it usually does. It makes him even more scared, knowing Dean is in danger, too, that Sam's pulled him closer to it. "Relax, Sammy, it's just a snake."

Dean leans over the pool, his amulet dangling in front of Sam's face, and Sam wants to tell him to get back, to run and save himself, but he can't get the words out and Dean is grinning like nothing's the matter and—

The snake rears up and punches forward, burying its fangs in Dean's neck.

Sam jerks awake, blinking the sleep out of his eyes, and sees Lucifer standing at the foot of his bed, grinning down at him with Cas's face.

He surges upward in his bed, really awake this time, a shout bursting from his lips and a jolt of pain running through his stomach. Just a dream, he tells himself. Except when Lucifer is involved, it being a dream doesn't mean it isn't real.

Heavy, stomping footsteps approach Sam's room. "Sam?!" Dean pounds on the door a few times before bursting in. He bounds over to the side of Sam's bed and starts pawing at Sam's shirt. "What? Did you tear your stiches or something?"

Sam slaps Dean's hands away. "No, no, man. I just…" he swallows down the lump in his throat and nods. "I just had a nightmare, that's all."

Lying to Dean about this stuff never ends well. Sam knows this, and he almost tells Dean about seeing Lucifer. Until he registers that Dean is in his jeans, with his boots still on, and he realizes that it's the middle of the night and Dean hasn't even _tried_ to get any sleep. He looks gray and drawn, and Sam knows how hard these last few days have been on Dean, how freaked out he was about Sam's injury and near death, how he was neglecting to take care of himself in favor of taking care of Sam.

"A nightmare," Dean repeats, blinking. "You _screamed_ , Sammy. A nightmare about wh—"

"Hey," Sam blurts out, cutting Dean off before he can finish the question. "Do you remember that case back in '92 or '93, the haunted lighthouse thing? It was killing kids, so Dad had us hang out at the tidal pools while he worked the job?"

"Yeah, I guess," Dean says, his brow furrowing. "Sammy, what—"

"You got bitten by a snake, remember?" Sam blows on, fighting back a flinch as the image of the thing arcing through the air, of Dean going white and clutching his wounded neck, flashed through his brain. "It really freaked me out."

"Oh, yeah, I remember that." Dean, a hint of a smirk creeping over his face. "You were bawlin' all the way to the emergency room. And it wasn't even a poisonous snake. The docs sent me away with some aspirin and a Band-Aid."

Sam nods. "I didn't like snakes. Still don't. That's what the nightmare was about."

"Uh huh." Dean still looks uneasy. "Well, do you need anything? More meds or something?"

"No," Sam lies. "No, I'm good."

* * *

The next day, Sam is lugging a stack of thick ledgers from the library to his room when he realizes that his gunshot wound doesn't hurt at all. Not even a twinge or a dull ache. Confused and a little freaked out, and he puts the ledgers on the table and runs his hand over his stomach. There are no stitches, not even a scar.

"What the hell…?"

"Hiya, Sammy. How's it going?"

Sam's head snaps up. Lucifer is standing in the library, not ten feet away from him, wearing Castiel's skin. Pure panic shoots through his bones before he realizes he's dreaming. "Get out of my head, you son of a bitch."

Lucifer fakes looking wounded. "What kind of welcome is that?" He snags a chair and plops down, swinging his legs up on the table. "You know, you should really be thanking me, Sammy."

A bitter laugh tears up Sam's throat. " _Thanking_ you? For what?"

"For bringing you back after that little mutt smothered you. Pretty undignified way to go, by the way. You really have gone downhill since I left you, kiddo."

" _What_?" Sam shakes his head disbelievingly. "I didn't die. I just went into shock and my heart rate slowed down."

Lucifer rolls his eyes. "Really, Sammy? Of course that's what the doctors told you. What did you expect them to say? No, you died and I brought you back. You're welcome."

"You expect me to believe that?" Sam spits. "Last time I saw you, you tried to _kill_ me."

"Okay, okay, you're right. I did." Lucifer lifts his legs off the table, leaning forward. "I admit it. I have some anger management issues. I'm working through them. But when I felt that you were gone, really _gone_ , I realized that I wanted you alive."

"Felt?" Sam repeats. His voice quivers, just a little.

"Of course. There's a connection between me and you, Sammy. I can feel what's happening to you."

Sam feels light-headed. "Why would you want me alive?"

"What can I say, Sammy?" Lucifer stands up, his chair screeching across the floor, and Sam flinches. The fact that Lucifer looks like _Cas_ just makes it so much worse. "I guess…" He starts strolling lazily around the table toward Sam, who tries not to but backs away anyway. "I guess I just realized that I would miss you, Sammy. I mean, you always used to plead so nicely. I realized I needed that in my life."

Sam's back hits a bookshelf, and Lucifer keeps coming. Nausea wracks his body, and he tries to shut down the part of his brain so he doesn't remember the Cage, doesn't remember that predatory smile, but he can't.

"And then there's the little matter of _this_." Lucifer grabs the collar of Cas's crisp white shirt and pulls it down. There's a large dark red spot marring his collar bone, a disgusting patch of damaged and peeling skin. "I may have miscalculated how long this body will hold me." He shrugs. "Oops. Turns out I may need a back-up plan."

Lucifer wants him as a vessel. Lucifer's out in the world and _wants him as a vessel_. "No. Never. _No_."

Lucifer smiles. "We'll see about that."

"No," Sam repeats. "That's never going to happen."

"We've been through this before, Sammy. And how did that end?"

"No, never again." Lucifer just keeps smiling at him, gentle and amused, like he's a child throwing a tantrum. "NO!"

" _Sammy_!"

Sam's eyes fly open and he's looking into Dean's panic-stricken face. The red of the burst vessels in the whites of his eyes contrasts sharply with the green of the irises. Dean's hands are gripping his shoulder, tight enough to hurt.

"What the hell, Sam?"

Sam stares up at him, taking in the lines in Dean's forehead, the unnatural pallor of his skin. "I had a nightmare," he says after a few seconds.

"No shit, Sam. I heard you screaming from the kitchen."

"I didn't mean to bother you. I'm sorry."

Dean blinks, his bloodshot eyes softening. He eases himself down onto the corner of Sam's bed, slowly enough to avoid rocking the bed with his weight, the way he does when he thinks Sam is falling apart.

"Tell me what's going on, Sammy," Dean says quietly. "Is this about the werewolf thing?"

Sam pulls himself up into a sitting position, sighing, knowing that this would double Dean's stress and hating himself for it. "It's not…Listen, don't freak out, it's just…"

Sam tells him, and Dean freaks out.

* * *

 _Thanks for reading! I'll post the next chapter in a few days, if people are interested._


	2. Evangelist

_A/N: Pretty much just angst this chapter. Resolution and comfort next chapter. It will be up in about a week, or sooner if I am motivated. (And reviews motivate me, hint, hint, extortion)._

 _Thank you so much to everyone who reviewed!_

 _WARNINGS: Violence and implied sexual violence._

Evangelist.

 _And the Lord said, behold,_ _Satan_ _hath desired_ _to have_ _you, that he may sift_ _you_ _as wheat._

 _Luke 22:31_

Dean paces around Sam's room, scrubbing his hands through his hair. "I could really use a fucking drink right now."

"Then have one," Sam says. If he was ever going to sanction Dean's problem-drinking, it would be now.

Dean's face tightens, just barely, but Sam notices it. Something's up with Dean, that much is obvious. Sam had expected Dean to drink himself stupid the night they got back to the bunker after the werewolf debacle, but Dean hadn't touched any alcohol. He hadn't even been taking pain pills for his ribs, although he'd tried to hide that from Sam. It has to be related to what Dean did when he thought Sam was dead—Sam hadn't for a second believed that Dean would leave him alone in a forest full of werewolves if he'd thought Sam was still alive—but Sam still couldn't figure it out.

"Nah, someone has to be sober here, with you whacked out on pain medication." Dean sighs. "So, what do we do? Up the angel warding?"

Sam picks at his blanket, smoothing and re-smoothing the corner down. "I don't think that will stop him from coming into my dreams."

"Okay, so we'll find a heavy-duty dream-catcher. The Men of Letters have to have something like that."

"That won't work either."

"How do you know that?" Dean demands.

"There's a special connection between angels and their former vessels, Dean," Sam replies softly. "A dream-catcher won't break it."

Dean's face twists, and he rubs at his eyes, looking for a moment like an overwhelmed kid. Like when he was eleven and Dad was late and the rent was due.

"Do you think this means Cas is dying?" Dean finally asks.

Sam stomach twists, forming a painful knot that his gunshot wound has nothing on, because yeah, it could mean that. Or it could mean that Lucifer is the only thing keeping Cas alive, and if they ever yanked Lucifer out of him…

Dean is staring at him, his bloodshot eyes ringed with black and full of growing despair. Dean needs to do something, Sam knows, or he'll drive himself crazy.

"We won't let that happen, right?" Sam says. "Let's just double down on figuring out how to get Cas back." Even though they've been looking into that for _months_ , with no leads. "I was thinking we could figure out a way to modify the syringe that Cas used to get Gadreel's grace out of me. Think you could look into how it works?"

The syringe won't work for full-on angel possession, Sam's pretty sure about that, but it might kept Dean busy and out of his own head for a few hours.

Dean nods slowly. "Yeah, okay. You just—just don't go to sleep for a while, alright?"

Sam give him a wane smile. "You don't have to tell me that."

* * *

But Sam can't stay awake forever, and after they've decked out Sam's room with a dream catcher from every culture from Hittite to Olmec and Sam's fifteen cups of coffee have worn off, he closes his burning eyes for just a minute, to rest.

And when he opens them, Lucifer is sitting across from him. "Look, Sammy," he says. "Not that I didn't enjoy this adorable hard-to-get act at first, but it's really starting to get old."

"I'm not going to say yes," Sam hisses. "Not _ever_."

"Not even to save Cas's life?" Lucifer counters. "You know, it's your fault I'm riding him in the first place. You're the one who thought God was talking to him. I mean, really, Sammy? After everything you've done?"

Sam clenches his jaw. He knows that, and it stabs him right in his chest, but he tries not to show it. "This is your new strategy, then? A guilt trip?"

Lucifer's eyes go soft and sad then, and he looks like Cas. "I wish I didn't have to, Sam. I wish you could just realize that you belong with me."

Sam's stomach churns. "You should just pick an angle and stick with it. This flip-flopping thing? It's really undercutting your message."

"You know nobody will ever love you as much as I do, Sammy," Lucifer murmurs, ignoring him. "Dean tries, I know he tries, but he'll always see you as the boy with the demon blood. He'll always resent you for taking away his childhood. No one else will love for who you are, _all_ of who you are. It's just me."

Lucifer used to talk like this when he was hurting Sam, when he was tearing his flesh and peeling his tendons out one by one. "God," Sam chokes out.

"God's gone, Sam. It's just me."

"This is so fucked up."

"No." Lucifer is suddenly at his side, his cold breath on Sam's neck. "This is how things are supposed to be. This is what _we're_ supposed to be."

"There's no _we_ ," Sam gasps. He tries to pull away, but Lucifer holds him in place, and fuck, fuck, Sam thought he'd never be in this position again. He thought he'd never be the helpless, desperate person he was in the Cage again.

"Of course there is," Lucifer whispers into his ear. "There always has been. I'll be back for you, Sammy. We'll be together soon."

Sam jolts awake, and his time he opens his eyes to see the top of Dean's head. Dean is slumped over his bed, his head resting by Sam's chest, but he's not sleeping. He's breathing harshly, and repeating something, over and over.

"Sammy…Sammy…"

"Dean?" Sam croaks.

Dean's head shoots up, his eyes wide and red-rimmed, full of relief and fear. "Sammy? Are you okay?"

"Yeah, yeah, 'course." Except his throat fucking hurts and when he blinks, he feels a hot tear roll down his face.

"You were shouting 'no' in your sleep," Dean mumbles. "I tried to wake you up, I tried everything I could think of, but you wouldn't. You just wouldn't."

"It's fine," Sam says, wiping the tears from his face. "I'm fine. It's okay."

"It's not fucking okay. That bastard, he took you and he took Cas and now he's…and I can't…" Dean's voice breaks. "I'm so sorry Sammy. I should be able to help you. I should be able to protect you."

"Dean," Sam says weakly. "Dean, it's not always on you. I can handle it." But he's not sure he can. The very idea of seeing Lucifer again, of being _touched_ by him again, is enough to fill him with fear. What if he betrays the world again? What if he betrays his _brother_ again?

Dean's always been the strong one, so if Dean's cracking, Sam knows he must not be far behind.

* * *

The visitations continue every time Sam closes his eyes. Lucifer threatens and cajoles and once he even pretends to be Castiel and pleads with Sam to please help him stop the Darkness.

Or at least, Sam hopes it was Lucifer pretending.

It's running Sam ragged, and Dean's not fairing much better. He spends all his time hovering by Sam's side, trying and failing to wake Sam from his nightmares. It becomes pretty clear that when Lucifer wants Sam, he can get him, and he can keep him.

And when Sam finds himself alone, without Dean at his elbow shaking him desperately to keep him awake, he knows he's back with Lucifer again. He drops his head onto the table, trying to shut out the dream. _Just make this end_ , he prays. _Please just make this end. I'm sorry. I can't take it anymore._

"If you want this to end, you know how, Sam," Lucifer says. "Just say yes. There's no other way to stop the Darkness, you know that. If you say no, you damn the world. Are you really that selfish?"

Maybe Sam should say yes. The more they research the more it becomes apparent that defeating Amara needs more power they have. But if Cas saying yes was tearing Dean apart, Sam saying yes would kill him. And he can't handle the idea of being under Lucifer's power again, of being his bitch.

Sam's always been selfish.

"No," Sam mumbles into his arms. "No."

Sam hears Lucifer sigh, a long, angry noise. "Okay. You want to do it that way? We'll do it that way."

Strong hands seize Sam's shoulders and haul him up. Sam wheels away, swinging his fist, but he's been knocked off his balance and he misses his mark completely. Lucifer doesn't have that problem, though. He punches Sam's face and it _hurts_. Sam didn't know he could hurt this much in a dream. And then Lucifer does it again and again until blood is running into Sam's eyes and his vision is swimming.

Lucifer grabs him by the front of his shirt and slams him against the wall. Sam thrusts his head forward and smashes it Lucifer's face, but the blow doesn't even slow the archangel down. He throws Sam away and his head strikes the corner of the table, and before Sam can even register the pain Lucifer seizes a handful of his hair and hauls him back up.

Lucifer slams Sam against the wall again and this time he pins him there, his hand wrapping around Sam's throat. Sam gasps, trying to prepare himself to be choked, but Lucifer just presses down, almost gently, not enough to stop him from breathing but enough to make it clear he could. Sam's pulse pounds underneath the archangel's fingers as he stares into Cas's deep blue eyes.

"Last chance," Lucifer murmurs. His free hand is resting on Sam's chest now, proprietorially. Sam scrabbles desperately at Lucifer's arms, but he can't move them, can't stop what's happening. He never could.

"Don't," Sam pants. "Don't."

"Answer me, Sammy." Lucifer squeezes his throat. "Now."

Tears are dripping down Sam's face, pain wracking his body, Lucifer getting angrier and angrier before him, and he's been here before. He knows how this ends. "No," he whispers. It's not the 'no' of topside Sam, the Sam who fights and survives and saves the world. It's the 'no' of Cage Sam who cries and begs and whimpers and then gets ripped apart anyway.

"When are you going to learn, Sammy?" Lucifer takes his hand from Sam's throat and wind into his hair. He jerks Sam's head back sharply. "You don't get to say no to me." He steps closer, so close their faces almost touch, and Sam's breath stutters in his chest. _Please, no,_ he thinks. _Not when he looks like Cas. Please._

"I guess I'll just have to remind you."


	3. Revelation

_A/N: Wow, this story got away from me. It was originally intended to be some straight hurt Sam, protective Dean, but in this chapter it turned into something bizarrely psychological. Sorry about that._

 _Technically the end, although I may do an epilogue._

Revelation

 _And he laid hold on the dragon,_ _that old serpent_ _, and bound him a thousand years._

 _Revelation 20:2_

" _Hey douchebag!_ "

Sam and Lucifer whip their heads around.

Dean is standing in the threshold of the library, his frame silhouetted by the lights, glaring at Lucifer like he could send him back to hell with the sheer force of his hate.

"You're gonna want to get your fucking hands off of him, _now_."

Lucifer is actually stunned into silence, and Sam stammers, "D-Dean…how…?"

Dean grins. "Little dreamroot, little hair, down the hatch. You really need to stop using that fruity girl shampoo, by the way. Gross, dude." He looks back to Lucifer. "Now, you can go ahead and get your feathery ass the fuck out of here."

All the anguish, all the helplessness and hopelessness, all the shadows that had hung over Dean's face are gone. His eyes are bright with purpose, and he looks larger than life as he strolls toward them. Sam feels like a kid, feels like he did when Dean could do everything and protect him from anything, when the simple presence of _Dean_ meant everything was going to be okay.

Lucifer is _pissed_. "I am _so_ — _fucking_ — _sick_ of you!" he snarls at Dean.

Lucifer's grip on Sam loosens, and Sam pulls himself away and stumbles toward Dean. Dean grabs Sam and pulls him back, clapping him on the shoulder.

"Go ahead and take a knee, Sammy. I got this one." Dean turns his attention back to Lucifer. "Oh, yeah, asshat? I'm not your biggest fan, either."

"How are you _always there_?" Lucifer snaps, sounding like a petulant child. "I'm in Stull Cemetery with my vessel, and you're there. I'm in hell with my vessel, and you're _there_. Why won't you just _go away_?"

"If Sam's there, I'm gonna be there, too," Dean says, without a hint of fear. "Always."

Lucifer glares at him, literally gnashing his teeth. With Dean standing there like a shield, sucking it all up and reradiating it as stark, come-and-fucking-get-me confidence, Lucifer's rage is kind of funny. Sam laughs, and Dean joins in and Lucifer gets even madder.

"This doesn't change anything," Lucifer spits. "I can still come into his dreams. You still need me. This vessel, your _best buddy_ , he's gonna die, soon."

Sam stiffens, his laughter dead and buried and putrefied in a second, and he looks to his brother. But Dean's not at all ruffled. "I know all that. And I'm gonna get you out of Cas. But here's the thing." Dean starts to walk lazily around the library, keeping himself between Sam and Lucifer. "You've got some freaky angel-possession connection thing going on with Sam? That's fine, because that kid's been in my back pocket since he was born and we share a heaven, so I figure our psychic-twin deal is a lot stronger than yours."

Lucifer's lips twist. "Sam's been mine since the beginning of time. He exists _for_ me, and _because of_ me. You are _nothing_ in this equation, do you understand? When will you—"

Lucifer stalks toward Dean, and Sam flinches, but the archangel never comes within swinging distance of his brother. Dean lifts a single hand, and Lucifer freezes.

"And you're an archangel and everything," Dean drawls, unconcerned, "so maybe you can pull a few tricks in here, keep Sam from waking up, make him feel pain, whatever. But that dreamroot I took? It's pretty powerful stuff. I can do things in here, too."

Dean snaps his fingers. One of the Men of Letters swords lifts up, whistles through the air, and impales Lucifer through the chest.

Lucifer, pinned to the wall like a bug specimen, spits out a mouthful of blood and then reaches down and slowly removes the blade from his body. "So this is your plan? A nightly cage match in your little brother's head?"

"That's Plan B, actually. Plan A—"

Sam doesn't hear Plan A, because Lucifer is suddenly right next to him and a cloud of mist blossoms between them and Dean. Sam hears one last panicked shout from Dean, sees Dean vault toward them, and then Dean is distant and unreachable, like they've been separated by a mile of ice.

"DEAN!"

Sam rushes forward, but there's something separating him from his brother. A wall.

"What the hell did you do?"

"Just a little angelic trick of the trade," Lucifer puffs, out of breath. "One of the things we use to keep our vessels' consciousness out of the way. I thought I could use it to let us talk."

While Lucifer watches him quietly, Sam punches the wall until his fingers break. Finally, he gives up, feeling a surge of despair so vast and crushing that it takes everything he has not to lie down on the ground and try to cease to exist.

"Sam," Lucifer says, soothingly, and Sam could almost believe that the archangel hadn't been about to brutalize him not five minutes ago. "I know this is hard. I know Dean's being here makes it harder. But you have to think about your brother."

Sam knows he should be telling Lucifer to fuck off and starting kicking the wall until he toes break too (that's what Dean would do), but he'd settle for not crying in front of the Devil, so instead he says "What?"

"You know Dean hasn't been right lately," Lucifer continues. "He hasn't been sleeping, he hasn't been drinking or taking his medicine… You know something is wrong with him, really wrong. You saw the bill from your fake insurance. Dean tried to hide it, but you saw it. What did it say?"

Answering Lucifer is automatic. It's a reflex like pulling your hand from a flame. Do it or pain will follow. "They pumped his stomach," Sam whispers.

"He tried to kill himself," Lucifer says, his voice still low and silky smooth and a twisted, pathetic part of Sam wants to find comfort in that almost-Cas voice. "And you drove him to that, Sam."

A sob breaks out of Sam's mouth.

"You're broken, Sam." Lucifer places a gentle hand on his shoulder, and Sam wants to push him off but he can't. He's exhausted, fucking exhausted from fighting so much for so long. And Dean had been here, which meant he was supposed to be _safe_. He wasn't supposed to have to do this on his own anymore. "You're broken. Dean's been holding you together, but's it's breaking him, too. You need to let him go, Sammy. I know you love him, but you're killing him."

Sam glances over to the smeared figure of Dean behind the blurry wall. "Dean needs me," he chokes out.

"No, Sam. Older brothers never need you as much as you think." Lucifer frowns, his eyes going distant for a moment. "Think, Sam. If you say yes, Dean will have Cas back. He'll have his best friend, a relationship that didn't come from obligation or orders from his father. We'll destroy the Darkness, together, and then he'll be free to do whatever he wants with his life. Isn't that the best thing you can give Dean? His freedom?"

Sam tries to pull the strands of this insanity together into a coherent picture, tries to penetrate through Lucifer's mind-fuckery to figure out his best move. He loves Dean and he wants to do the right thing. He feels dizzy.

"I'll tell you this, Sammy. I'm broken, too. We can hold each other together. No more being alone."

Sam looks up into Lucifer's eyes and sees something new. No anger, no contempt or hate or sarcasm or sadness. Desperation. And then he glances over to where Dean is waiting for him on the other side of the wall, because he plunged himself into Sam's fucked up head to go hand-to-hand with Satan.

Sam straightens himself to his full height, takes a step back to meet Lucifer face-to-face, and then he hurls himself at the wall.

His head shatters the surface at impact, and then it's pressure and viscosity and for a moment he feels a powerful sensation of suspension, of lack of identity, of existence without life. It's almost pleasant in its numbness. But the pressure is warm because it's crushing him and he can see something on the other side, something reaching for him, something calling for him, and he struggles through the blur and the flog and—

Sam bursts out into Dean's arms. They both crash down to their knees.

"Sam?" Dean gasps. "Are you okay?" They haul each other to their feet.

"Yeah," Sam says. He can feel something pulsing under his collarbone, something warm and electric.

"Sam! We're not finished here." Lucifer is back, as furious as he's ever been, looming over them, but Sam doesn't feel that usual deep-seated fear, that primal impulse to bear his throat and take his punishment. He has Dean by his side. In an instant, he knows he's not going to say yes.

Lucifer is just as scared and lost as the rest of them, so why should Sam be afraid of him?

"Yeah, we are," Sam tells him. "We're finished."

"Time for Plan A," Dean adds. Dean pushes against him so they're shoulder to shoulder. "This is your head, Sammy. Cast him out. I'm here to back you up."

"Please." Lucifer barks out an ugly laugh. "This is your plan? Sheer force of Sammy's will?"

"Sam's will was enough to put you away before," Dean retorts. Sam closes his eyes, trying to focus. _Get out of my head. You're not welcome here. Get out of my head._

"Sure," Lucifer hisses. "But that was before I got my hooks into him. We both know what a good couple centuries on the rack can do to a person, right, Dean? I tore your little brother apart, peeled off all those fleshy red muscles, you know the ones, and I let him taste them, and I burned up the wounds to that perfect crisp, and then the grand finale, and, _oh_ , Dean, the pretty little sounds he made when he begged me to stop, you've never heard anything like it—"

" _Shut up_!" Dean shouts, and Lucifer's jaw clamps shut.

Sam's shaking by now, his rhythm broken, and Dean grabs his arm and he keeps going.

"Get out of my head, Lucifer. Get of out my head, Satan. Helel, Beliar, Beelzebub, Mastema, you're not welcome here. GET OUT!"

Sam squeezes his eyes shut, feels Dean's vice-grip on his arm, feel's his brother's warmth pressing into his side. He remembers that day by the tidal pools, how Dean listened to him babble on about crabs and sea turtles and the moon, how Dean bullshitted about the kraken life-cycle to calm Sam down in the emergency room while his snakebite got treated.

Sam opens his eyes and fixes them on Lucifer. "I'm not yours. Get the hell out."

* * *

Lucifer finds himself expelled and alone on the outskirts of hell, and Sam and Dean wake up in the Bunker, exhausted and weighed down and together.

 _A friend loves at all times, and a brother is born for adversity._

 _Proverbs 17:17_


End file.
